New growth will make dreads all on it's own. I have lots of little babies that just formed on their own. I can count over 20 right now. I see strands of new growth on your head that has already started little sections. Those little strands will knot up naturally. If you feel the need to do something with the new growth, I would recommend twist and rip over backcombing. I don't think it is ok to use a hook ever. Either way...good luck with it